There's a difference between sorting out the pecking order and outright bullying, it's good you've taken a stance against nasty chooks. Even if a chook's sick or injured I don't tolerate bullies because while that's natural in the wild, they're not in the wild, and it's my choice which injured/sick chook gets culled, not theirs. If you don't keep bullies and don't breed bullies, you won't have bullies. It's entirely possible to have a huge flock of all ages, breeds and genders together in peace, as long as you don't tolerate or breed vicious or violent birds and meet their space and feed requirements. In my experience there isn't actually any breed that is inherently violent, it's the breeder's strain and the environment they're raised in that does it. Not that I'd vouch for the wild ancestors of chooks in captivity, I reckon you probably wouldn't have much luck there.
Even if you have a cockerel, there will always be a dominant hen, though, who will be a bit inclined to strong-arming her way to maintaining status. Having no males around can be quieter, but when you have girls who are high on maternal instinct, they'll get cranky or worse, mopey, for lack of a male. Battery hens won't care, generally, you have to feed them a year's worth of regular kelp before they even understand what a male is for.

Really instinctive hens will cope without a male if you've never had one, but once they get used to the idea, some may even abandon your property if you remove the male and don't replace/return him. Also some of the more instinctive will abandon your place with the male of their choosing if you make too obvious a habit of taking away/eating their favourites. I've left breeding pairs of newly feral chickens in a few places I've lived... Not deliberately!

Too much kelp makes them too smart, or something.